Darab Plain is among region that in there formed several alluvial fans because presence of situation and climate change, and can mention to Katoeh, Rigabad and Chenar alluvial fans. In this research is tried to using of Geology and Topographic Maps, Arial Image ana Field survey analysis are discussed  Factors affecting the establishment and evolution of this alluvial fans. Result showed that Katoe and Chenar Rivers have high pure force because sharp steep of bed and increase of velocity, and is Prevailing practice of digging the river bed because excess of force that was transfers the downstream materials from erosion. This agent was caused formation of case study alluvial fans. Alluvial fans morphology of Katoe and Chenar has the unique feature. because deposition act don’t in an open space by Katoe and Chenar rivers, but was limited the left side of katoe alluvial fan by Noro mountain and right side of Chenar alluvial fan with Barfdan Mountain. Also human disarranged natural order of case study alluvial fans evolution with creation of artificial embankments, and sand removal